Various electronic apparatuses are mounted at an automobile. An electric connection box supplying electric power and transmitting data signals to the various electronic apparatuses are provided suitably at suitable positions in the automobile. In the present invention, a junction block (or junction box), fuse block (fuse box) and relay block (relay box) are called an electric connection box as a generic name hereafter.
The electric connection box has various structure according to a model of the automobile. For example, the electric connection box has a fuse block 201 mounted at a circuit board 213 for distributing electric power supply (see Patent Document 1).
The fuse block 201 is formed by a metal plate, and includes a plurality of busbars 202, 203, 204, 205 bent into L-shape and a hold member 214 made of synthetic resin for holding the busbars 202, 203, 204 and 205. Each of busbars 202, 203, 204 and 205 is provided at one end thereof with at least one tuning-fork shaped connecting portion 206 to be connected with a fuse 209, and at the other end thereof with at least one board connecting portion 207 to be connected with a printed circuit board 213 by soldering. In FIG. 10, a joint portion 208 between the tuning-fork shaped connecting portion 206 and the board connecting portion 207 is shown.
The busbars 202, 203, 204 and 205 are arranged in parallel along a direction X and overlapped to form four layers along a direction Y. In other words, the busbars, in which the tuning-fork shaped connecting portions 206 are arranged in parallel along the direction X, are overlapped into four layers along the direction Y, and the four board connecting portions 207 provided in a line perpendicular to the direction X are arranged in a row along a direction Z.